Brønsted Acid-Catalyzed, Highly Enantioselective Addition of Enamides to In Situ<i>-</i>Generated<i>ortho</i>-Quinone Methides: A Domino Approach to Complex Acetamidotetrahydroxanthenes
作者:Satyajit Saha、Christoph Schneider
DOI:10.1002/chem.201406044
日期:2015.2.2
The highly enantioselective conjugate addition of enamides and enecarbamates to in situ‐generated ortho‐quinone methides, upon subsequent N,O‐acetalization, gives rise to acetamido‐substituted tetrahydroxanthenes with generally excellent enantio‐ and diastereoselectivities. A chiral BINOL‐based phosphoric acid catalyst controls the enantioselectivity of the carbon–carbon bond‐forming event. The products
cycloaddition of β-substituted ene- and thioenecarbamates as well as cyclic enamides with quinone diimides catalyzed by a BINOL- and SPINOL-derived phosphoric acid is reported. A wide variety of 2,3-disubstituted 2-aminoindolines, including polycyclic ones, were prepared in generally high yields (up to 98%) with moderate to complete diastereoselectivities and in most cases excellent enantioselectivities
Trimethylchlorosilane-promoted aza-Mannich reaction of enecarbamates and aldimines
作者:Pengcheng Wu、Deqin Lin、Xiaoxia Lu、Li Zhou、Jian Sun
DOI:10.1016/j.tetlet.2009.09.097
日期:2009.12
A trimethylchlorosilane-promoted aza-Mannich reaction is reported utilizing enecarbamates as the nucleophile and aromatic N-Boc aldimines as the electrophile. A variety of nucleophiles and electrophiles are tolerated by the reaction conditions, delivering the adduct products in excellent yields with high E-stereoselectivities. (C) 2009 Elsevier Ltd. All rights reserved.
Preparation and Allylation of Enamides and Enecarbamates Generated via Iron(0) Reduction of Oximes and Derivatives
作者:Steven Weinreb、Cuixiang Sun
DOI:10.1055/s-2006-942513
日期:2006.11
Reductive acylation of oximes and oxime carbonates can be effected with iron powder in the presence of an acid chloride or a chloroformate to produce enamides or enecarbamates.
用铁粉在酸氯化物或氯甲酸酯存在下进行亚胺和亚胺碳酸酯的还原酰化,可生产出烯酰胺或烯碳酸酯。
Methyltrichlorosilane-DMSO: A Facile and Highly Efficient Recipe for the Chlorination of Enamides and Enecarbamates
作者:Xiaoxia Lu、Jian Sun、Deqing Lin、Ke Cheng
DOI:10.1055/s-0029-1218005
日期:2009.11
A facile and highly efficient method was developed for the chlorination of enamides and enecarbamates with the combined use of methyltrichlorosilane and DMSO, which allowed one-pot production of the corresponding β-chloro enamides and enecarbamates in high yield and good stereoselectivity. This method is easy to operate and suitable for both cyclic and acyclic substrates.